The assessment of sexual differences in glioblastoma growth and therapy response has received little attention. We assessed the influence of sex in the MRI features of an orthotropic GBM rat model submitted to anti-inflammatory therapy. Multiparametric MRI studies were acquired at an early and advanced tumor stage of development. GBMs in untreated males presented a more aggressive pattern – worsened as the tumor progressed – than females. While treated males revealed a positive response to meloxicam treatment, females did not. Our results highlighted that sex is a relevant factor to be considered in GBM outcome and anti-inflammatory therapy success.